Granulocyte and monocyte adsorption apheresis (GCAP) is an extracorporeal circulation therapy that removes activated granulocytes and monocytes. GCAP was initially approved for the treatment of ulcerative colitis, which is attributed to activated granulocytes and macrophages that infiltrate the target tissues. Generalized pustular psoriasis (GPP) is also supposed to be caused by activated neutrophils. In this study, we treated two patients with refractory GPP by using GCAP. Patient 1, a 68-year-old woman who had liver cirrhosis, underwent seven GCAP sessions. Patient 2, a 26-year-old woman who had systemic lupus erythematosus and had been treated with systemic corticosteroids, underwent eight GCAP sessions. In both patients, GCAP resulted in an immediate improvement in skin lesions and fever reduction, without any adverse effects. We suggest that GCAP is an effective therapy for refractory GPP.